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authorstigge@antcom.de <stigge@antcom.de>2011-01-20 18:42:55 +0100
committerGuenter Roeck <guenter.roeck@ericsson.com>2011-03-14 22:36:24 -0700
commita5b79d62f2e6d1b0d44bcdafce46f47bf355b9fe (patch)
treedc918d8203b45d5dd4cd98e82ebd5f30bad0c94b /drivers/hwmon/max6639.c
parent521cb40b0c44418a4fd36dc633f575813d59a43d (diff)
hwmon: Driver for Maxim MAX6639
2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller Signed-off-by: Roland Stigge <stigge@antcom.de> Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Diffstat (limited to 'drivers/hwmon/max6639.c')
-rw-r--r--drivers/hwmon/max6639.c639
1 files changed, 639 insertions, 0 deletions
diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
new file mode 100644
index 000000000000..40fd878e53dc
--- /dev/null
+++ b/drivers/hwmon/max6639.c
@@ -0,0 +1,639 @@
+/*
+ * max6639.c - Support for Maxim MAX6639
+ *
+ * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
+ *
+ * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
+ *
+ * based on the initial MAX6639 support from semptian.net
+ * by He Changqing <hechangqing@semptian.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/i2c/max6639.h>
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
+
+/* The MAX6639 registers, valid channel numbers: 0, 1 */
+#define MAX6639_REG_TEMP(ch) (0x00 + (ch))
+#define MAX6639_REG_STATUS 0x02
+#define MAX6639_REG_OUTPUT_MASK 0x03
+#define MAX6639_REG_GCONFIG 0x04
+#define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
+#define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
+#define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
+#define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
+#define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
+#define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
+#define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
+#define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
+#define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
+#define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
+#define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
+#define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
+#define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
+#define MAX6639_REG_DEVID 0x3D
+#define MAX6639_REG_MANUID 0x3E
+#define MAX6639_REG_DEVREV 0x3F
+
+/* Register bits */
+#define MAX6639_GCONFIG_STANDBY 0x80
+#define MAX6639_GCONFIG_POR 0x40
+#define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
+#define MAX6639_GCONFIG_CH2_LOCAL 0x10
+
+#define MAX6639_FAN_CONFIG1_PWM 0x80
+
+static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
+
+#define FAN_FROM_REG(val, div, rpm_range) ((val) == 0 ? -1 : \
+ (val) == 255 ? 0 : (rpm_ranges[rpm_range] * 30) / ((div + 1) * (val)))
+#define TEMP_LIMIT_TO_REG(val) SENSORS_LIMIT((val) / 1000, 0, 255)
+
+/*
+ * Client data (each client gets its own)
+ */
+struct max6639_data {
+ struct device *hwmon_dev;
+ struct mutex update_lock;
+ char valid; /* !=0 if following fields are valid */
+ unsigned long last_updated; /* In jiffies */
+
+ /* Register values sampled regularly */
+ u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */
+ bool temp_fault[2]; /* Detected temperature diode failure */
+ u8 fan[2]; /* Register value: TACH count for fans >=30 */
+ u8 status; /* Detected channel alarms and fan failures */
+
+ /* Register values only written to */
+ u8 pwm[2]; /* Register value: Duty cycle 0..120 */
+ u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
+ u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
+ u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */
+
+ /* Register values initialized only once */
+ u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
+ u8 rpm_range; /* Index in above rpm_ranges table */
+};
+
+static struct max6639_data *max6639_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct max6639_data *ret = data;
+ int i;
+ int status_reg;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
+ int res;
+
+ dev_dbg(&client->dev, "Starting max6639 update\n");
+
+ status_reg = i2c_smbus_read_byte_data(client,
+ MAX6639_REG_STATUS);
+ if (status_reg < 0) {
+ ret = ERR_PTR(status_reg);
+ goto abort;
+ }
+
+ data->status = status_reg;
+
+ for (i = 0; i < 2; i++) {
+ res = i2c_smbus_read_byte_data(client,
+ MAX6639_REG_FAN_CNT(i));
+ if (res < 0) {
+ ret = ERR_PTR(res);
+ goto abort;
+ }
+ data->fan[i] = res;
+
+ res = i2c_smbus_read_byte_data(client,
+ MAX6639_REG_TEMP_EXT(i));
+ if (res < 0) {
+ ret = ERR_PTR(res);
+ goto abort;
+ }
+ data->temp[i] = res >> 5;
+ data->temp_fault[i] = res & 0x01;
+
+ res = i2c_smbus_read_byte_data(client,
+ MAX6639_REG_TEMP(i));
+ if (res < 0) {
+ ret = ERR_PTR(res);
+ goto abort;
+ }
+ data->temp[i] |= res << 3;
+ }
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+abort:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+static ssize_t show_temp_input(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ long temp;
+ struct max6639_data *data = max6639_update_device(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ temp = data->temp[attr->index] * 125;
+ return sprintf(buf, "%ld\n", temp);
+}
+
+static ssize_t show_temp_fault(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct max6639_data *data = max6639_update_device(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ return sprintf(buf, "%d\n", data->temp_fault[attr->index]);
+}
+
+static ssize_t show_temp_max(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000));
+}
+
+static ssize_t set_temp_max(struct device *dev,
+ struct device_attribute *dev_attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned long val;
+ int res;
+
+ res = strict_strtoul(buf, 10, &val);
+ if (res)
+ return res;
+
+ mutex_lock(&data->update_lock);
+ data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val);
+ i2c_smbus_write_byte_data(client,
+ MAX6639_REG_THERM_LIMIT(attr->index),
+ data->temp_therm[attr->index]);
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t show_temp_crit(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000));
+}
+
+static ssize_t set_temp_crit(struct device *dev,
+ struct device_attribute *dev_attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned long val;
+ int res;
+
+ res = strict_strtoul(buf, 10, &val);
+ if (res)
+ return res;
+
+ mutex_lock(&data->update_lock);
+ data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val);
+ i2c_smbus_write_byte_data(client,
+ MAX6639_REG_ALERT_LIMIT(attr->index),
+ data->temp_alert[attr->index]);
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t show_temp_emergency(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000));
+}
+
+static ssize_t set_temp_emergency(struct device *dev,
+ struct device_attribute *dev_attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned long val;
+ int res;
+
+ res = strict_strtoul(buf, 10, &val);
+ if (res)
+ return res;
+
+ mutex_lock(&data->update_lock);
+ data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val);
+ i2c_smbus_write_byte_data(client,
+ MAX6639_REG_OT_LIMIT(attr->index),
+ data->temp_ot[attr->index]);
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t show_pwm(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
+}
+
+static ssize_t set_pwm(struct device *dev,
+ struct device_attribute *dev_attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+ unsigned long val;
+ int res;
+
+ res = strict_strtoul(buf, 10, &val);
+ if (res)
+ return res;
+
+ val = SENSORS_LIMIT(val, 0, 255);
+
+ mutex_lock(&data->update_lock);
+ data->pwm[attr->index] = (u8)(val * 120 / 255);
+ i2c_smbus_write_byte_data(client,
+ MAX6639_REG_TARGTDUTY(attr->index),
+ data->pwm[attr->index]);
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t show_fan_input(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct max6639_data *data = max6639_update_device(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
+ data->ppr, data->rpm_range));
+}
+
+static ssize_t show_alarm(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct max6639_data *data = max6639_update_device(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index)));
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
+ set_temp_max, 0);
+static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
+ set_temp_max, 1);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit,
+ set_temp_crit, 0);
+static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit,
+ set_temp_crit, 1);
+static SENSOR_DEVICE_ATTR(temp1_emergency, S_IWUSR | S_IRUGO,
+ show_temp_emergency, set_temp_emergency, 0);
+static SENSOR_DEVICE_ATTR(temp2_emergency, S_IWUSR | S_IRUGO,
+ show_temp_emergency, set_temp_emergency, 1);
+static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0);
+static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1);
+static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 7);
+static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_alarm, NULL, 5);
+static SENSOR_DEVICE_ATTR(temp2_emergency_alarm, S_IRUGO, show_alarm, NULL, 4);
+
+
+static struct attribute *max6639_attributes[] = {
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp2_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_fault.dev_attr.attr,
+ &sensor_dev_attr_temp2_fault.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp2_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit.dev_attr.attr,
+ &sensor_dev_attr_temp2_crit.dev_attr.attr,
+ &sensor_dev_attr_temp1_emergency.dev_attr.attr,
+ &sensor_dev_attr_temp2_emergency.dev_attr.attr,
+ &sensor_dev_attr_pwm1.dev_attr.attr,
+ &sensor_dev_attr_pwm2.dev_attr.attr,
+ &sensor_dev_attr_fan1_input.dev_attr.attr,
+ &sensor_dev_attr_fan2_input.dev_attr.attr,
+ &sensor_dev_attr_fan1_fault.dev_attr.attr,
+ &sensor_dev_attr_fan2_fault.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group max6639_group = {
+ .attrs = max6639_attributes,
+};
+
+/*
+ * returns respective index in rpm_ranges table
+ * 1 by default on invalid range
+ */
+static int rpm_range_to_reg(int range)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
+ if (rpm_ranges[i] == range)
+ return i;
+ }
+
+ return 1; /* default: 4000 RPM */
+}
+
+static int max6639_init_client(struct i2c_client *client)
+{
+ struct max6639_data *data = i2c_get_clientdata(client);
+ struct max6639_platform_data *max6639_info =
+ client->dev.platform_data;
+ int i = 0;
+ int rpm_range = 1; /* default: 4000 RPM */
+ int err = 0;
+
+ /* Reset chip to default values */
+ err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
+ MAX6639_GCONFIG_POR);
+ if (err)
+ goto exit;
+
+ /* Fans pulse per revolution is 2 by default */
+ if (max6639_info && max6639_info->ppr > 0 &&
+ max6639_info->ppr < 5)
+ data->ppr = max6639_info->ppr;
+ else
+ data->ppr = 2;
+ data->ppr -= 1;
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_PPR(i),
+ data->ppr << 5);
+ if (err)
+ goto exit;
+
+ if (max6639_info)
+ rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
+ data->rpm_range = rpm_range;
+
+ for (i = 0; i < 2; i++) {
+
+ /* Fans config PWM, RPM */
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_CONFIG1(i),
+ MAX6639_FAN_CONFIG1_PWM | rpm_range);
+ if (err)
+ goto exit;
+
+ /* Fans PWM polarity high by default */
+ if (max6639_info && max6639_info->pwm_polarity == 0)
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_CONFIG2a(i), 0x00);
+ else
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_CONFIG2a(i), 0x02);
+ if (err)
+ goto exit;
+
+ /* Max. temp. 80C/90C/100C */
+ data->temp_therm[i] = 80;
+ data->temp_alert[i] = 90;
+ data->temp_ot[i] = 100;
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_THERM_LIMIT(i),
+ data->temp_therm[i]);
+ if (err)
+ goto exit;
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_ALERT_LIMIT(i),
+ data->temp_alert[i]);
+ if (err)
+ goto exit;
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
+ if (err)
+ goto exit;
+
+ /* PWM 120/120 (i.e. 100%) */
+ data->pwm[i] = 120;
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
+ if (err)
+ goto exit;
+ }
+ /* Start monitoring */
+ err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
+ MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL);
+exit:
+ return err;
+}
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int max6639_detect(struct i2c_client *client,
+ struct i2c_board_info *info)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ int dev_id, manu_id;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ /* Actual detection via device and manufacturer ID */
+ dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
+ manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
+ if (dev_id != 0x58 || manu_id != 0x4D)
+ return -ENODEV;
+
+ strlcpy(info->type, "max6639", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static int max6639_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max6639_data *data;
+ int err;
+
+ data = kzalloc(sizeof(struct max6639_data), GFP_KERNEL);
+ if (!data) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->update_lock);
+
+ /* Initialize the max6639 chip */
+ err = max6639_init_client(client);
+ if (err < 0)
+ goto error_free;
+
+ /* Register sysfs hooks */
+ err = sysfs_create_group(&client->dev.kobj, &max6639_group);
+ if (err)
+ goto error_free;
+
+ data->hwmon_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ err = PTR_ERR(data->hwmon_dev);
+ goto error_remove;
+ }
+
+ dev_info(&client->dev, "temperature sensor and fan control found\n");
+
+ return 0;
+
+error_remove:
+ sysfs_remove_group(&client->dev.kobj, &max6639_group);
+error_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int max6639_remove(struct i2c_client *client)
+{
+ struct max6639_data *data = i2c_get_clientdata(client);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&client->dev.kobj, &max6639_group);
+
+ kfree(data);
+ return 0;
+}
+
+static int max6639_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
+ if (data < 0)
+ return data;
+
+ return i2c_smbus_write_byte_data(client,
+ MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY);
+}
+
+static int max6639_resume(struct i2c_client *client)
+{
+ int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
+ if (data < 0)
+ return data;
+
+ return i2c_smbus_write_byte_data(client,
+ MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY);
+}
+
+static const struct i2c_device_id max6639_id[] = {
+ {"max6639", 0},
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, max6639_id);
+
+static struct i2c_driver max6639_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "max6639",
+ },
+ .probe = max6639_probe,
+ .remove = max6639_remove,
+ .suspend = max6639_suspend,
+ .resume = max6639_resume,
+ .id_table = max6639_id,
+ .detect = max6639_detect,
+ .address_list = normal_i2c,
+};
+
+static int __init max6639_init(void)
+{
+ return i2c_add_driver(&max6639_driver);
+}
+
+static void __exit max6639_exit(void)
+{
+ i2c_del_driver(&max6639_driver);
+}
+
+MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
+MODULE_DESCRIPTION("max6639 driver");
+MODULE_LICENSE("GPL");
+
+module_init(max6639_init);
+module_exit(max6639_exit);